Hair route

时间：2019-03-07 03:07:00166网络整理admin

By Philip Cohen PEOPLE have pampered, plucked and styled their hair for the sake of vanity for centuries. Now it could be put to a more noble purpose—as a cheap and painless way to administer vaccines. About seven years ago, scientists discovered that injecting purified genes from a virus could immunise animals against the live virus. This trick works because the DNA produces viral proteins, which spur the immune system into action. One attraction of this approach is that DNA vaccines are far cheaper to produce than conventional ones. Paul Khavari of Stanford University was looking for a way to get DNA into the body without needles. He rubbed DNA on the skin of mice as a negative control for other techniques, thinking it would not work. But as Khavari and his colleagues report in Nature Biotechnology (vol 17, p 870), the DNA entered cells and primed the rodents’ immune system to react to the viral protein it coded for. “It was a bizarre thing we couldn’t explain and we didn’t believe,” says Khavari. It turned out that the DNA was getting in through hair follicles. Mice that lacked follicles did not take up the DNA. However, while mouse and human skin are similar, it remains to be seen if human follicles can also act as DNA gateways. Jonathan Vogel, a skin specialist at the National Cancer Institute near Washington DC, calls the approach promising. “Imagine a vaccine you can deliver on a patch,